GLENWOOD SPRINGS, Colo. (CBS4) – Since opening over a decade ago, the Glenwood Caverns above Glenwood Springs have given visitors the opportunity to go deep underground inside the Rocky Mountains. But the lights that allowed people to see where they are going started causing some damage to the caves.

New technology is now saving a work of art millions of years in the making.

Inside the dark, deep, damp world of the Glenwood Caverns the old incandescent lights started becoming a big problem.

“Over the years in certain areas … we started to see some drying out,” Glenwood Caverns owner Steve Beckley said. “A lot of it was in the light bulbs and stuff because we have 300 light fixtures under the cave.”

The problem in the cave with keeping the incandescent light is that the rock formations grow very slowly over time and without a change they would have become extinct.

“The formations are still active and still growing,” Beckley said. “But if the cave dries out the formations are done growing and basically the cave becomes dead.”

“As soon as we found out that the caves had 75 to 100 watt incandescent bulbs, and 300 plus of them, we knew this was going to be an easier opportunity than maybe some of the others,” Erica Sporhawk with Garfield Clean Energy Challenge said.

With the help of the Garfield Clean Energy Challenge, they found the answer was LED lights. They cost up to $50 each, but use 80 percent less energy, last a few years longer than incandescent lights, and emit significantly less heat, helping the cave stay moist and the owner a little richer.

“They’ve estimated between the savings on electricity and the maintenance costs, about $12,000 a year,” Sporhawk said.

Beckley says the cost savings will help him add rides to the adventure park. But seeing water return to formations in the cave that were drying out is priceless.

The Glenwood Caverns started as a tourist destination in the late 1800s, but was shut down before the Great Depression. It reopened in 1999. The current owners hope to expand to even more areas of the cave next year.